{ "vercy": "1.0-draft", "publication": { "status": "research-draft", "adjudicationStatus": "unreviewed", "publishableCanonical": false, "generatedAt": "2026-09-12T10:58:29Z", "providers": [ "Codex" ], "breadth": "recalled by Codex without web access - no source was read", "missingProviders": [], "pass": 2, "cost": { "grok": { "seconds": 26.0, "error": "Reading additional input from stdin...\nOpenAI Codex v0.153.4\n--------\nworkdir: R:\\02_PROJECTS\\02_Meta_Models_Platforms\\Ver.cy\\current\\thing-registry-backlog\nmodel: gpt-6-astra\nprovider: openai\napproval: never\nsandbox: read-only\nreasoning effort: none\nreasoning summaries: none\nsession id: 01a09543-9155-7830-8d4e-7c657ffe161b\n--------\nuser\nDescribe what is already known about one registered thing. Answer as JSON only, no prose around it.\n\nThing: linear energy transfer\nSense to describe: (none recorded)\nDomain code: XCT.QLT\nAlso known as: (none)\n\n\nContext for this batch of 1001 things:\n# Batch 04", "usd": 0.0, "recall": true }, "codex": { "seconds": 82.0, "error": "Reading additional input from stdin...\nOpenAI Codex v0.153.4\n--------\nworkdir: R:\\02_PROJECTS\\02_Meta_Models_Platforms\\Ver.cy\\current\\thing-registry-backlog\nmodel: gpt-6-astra\nprovider: openai\napproval: never\nsandbox: read-only\nreasoning effort: none\nreasoning summaries: none\nsession id: 01a09543-9148-7b23-b9b8-37da8786d7c1\n--------\nuser\nYou are drafting a Vercy meta-model for one registered thing. Answer as JSON only, no prose around it.\n\nThing: linear energy transfer\nRegistry id: vr.tr.linear-energy-transfer\nPlane / domain: XCT / XCT.QLT\nRegistry definition: (none recorded)\nNames folded into" } }, "enrichment": { "pass": 3, "engine": "claude", "producedAt": "2026-10-06T12:00:00Z", "ingestedAt": "2026-10-06T08:39:46+00:00", "fields": [ "agent_conduct", "ethics", "failure_modes_and_hazards", "owners", "standards_and_regulation", "visual_identification" ] }, "gate": { "passed": true, "version": "1.0", "at": "2026-10-07T10:10:26+00:00", "evidence": [ "completeness 1.00", "sense: Wikidata description", "2 live sources", "review by codex: pass" ] } }, "metaModel": { "id": "THING-Q1699996", "registryId": "vr.tr.linear-energy-transfer", "name": "linear energy transfer", "version": "0.1.0-research.1", "entryKind": "thing", "family": "Thing Registry", "domain": [ "XCT.QLT" ], "status": "research-draft" }, "canonicalUrl": "https://ver.cy/models/thing/q1699996/", "model": { "registry_id": "vr.tr.linear-energy-transfer", "name": "linear energy transfer", "purpose": "Enable an agent to identify, compare and use linear energy transfer descriptions while preserving the particle, material, restriction and averaging conditions that give each value meaning.", "definition": "Linear energy transfer (LET) is the mean energy lost by a charged particle through electronic interactions per unit path length in a specified material, with restricted LET excluding energy carried away by secondary electrons whose kinetic energies exceed a specified cutoff.", "scope_statement": "This model owns linear energy transfer as the registered physical quantity vr.tr.linear-energy-transfer, including its definitions, conditioned values, spectra, estimation methods and limits of interpretation.", "in_scope": [ "Restricted and unrestricted LET definitions and their stated conventions", "Dependence on charged-particle species, kinetic energy and traversed material", "LET values, spectra and spatial distributions", "Track-weighted and dose-weighted LET summaries", "Measurement inference, calculation settings and uncertainty", "Conditions for comparing LET or using it in radiation-effect models" ], "out_of_scope": [ "Complete models of particle beams, accelerators and irradiation facilities", "Absorbed dose, equivalent dose and radiation protection quantities as independent concepts", "Complete stopping-power and particle-range models", "Microdosimetric lineal-energy and specific-energy distributions as independent quantities", "Biological damage mechanisms and relative biological effectiveness models", "Detector construction and clinical treatment prescriptions" ], "distinguishing_features": [ "A LET value describes energy transfer per charged-particle path length; it is not absorbed energy per unit mass.", "Unrestricted LET corresponds numerically to electronic collision stopping power, rather than stopping power including every loss mechanism. [NIST stopping-power report](https://nvlpubs.nist.gov/nistpubs/Legacy/IR/nbsir82-2550A.pdf)", "Restricted LET requires a declared secondary-electron energy cutoff and restriction convention; a bare number does not establish which quantity was reported.", "Lineal energy uses single-event energy imparted to a finite site divided by its mean chord length; matching units do not make it LET. [Microdosimetry uncertainty study](https://doi.org/10.1088/1361-6560/AC79FB)", "A beam-level average requires a weighting rule and included particle population; the label LET alone does not identify that average." ], "characteristics": [ { "name": "LET magnitude", "kind": "measurement", "unit_or_values": "keV/µm or J/m, with uncertainty", "why_it_matters": "Provides the numerical quantity after its defining conditions are established." }, { "name": "Restriction convention", "kind": "category", "unit_or_values": "Restricted LΔ; unrestricted L∞; explicitly documented alternative; unspecified", "why_it_matters": "Determines which electronic energy transfers contribute." }, { "name": "Secondary-electron cutoff", "kind": "measurement", "unit_or_values": "eV or keV; infinity for unrestricted LET", "why_it_matters": "Makes a restricted value interpretable and reproducible." }, { "name": "Charged-particle population", "kind": "relation", "unit_or_values": "Species and included primary, secondary and fragment populations", "why_it_matters": "Identifies whose tracks the LET describes." }, { "name": "Particle kinetic energy", "kind": "measurement", "unit_or_values": "eV, keV or MeV; MeV/u explicitly distinguished", "why_it_matters": "Conditions the particle's LET at the location being described." }, { "name": "Reference material", "kind": "relation", "unit_or_values": "Material identity, composition, density and relevant physical state", "why_it_matters": "Prevents treating LET as a particle property independent of its medium." }, { "name": "Averaging convention", "kind": "category", "unit_or_values": "Unaveraged conditioned value; track-weighted; dose-weighted; other explicit estimator", "why_it_matters": "Identifies how heterogeneous tracks are reduced to a reported statistic." }, { "name": "Spatial support", "kind": "relation", "unit_or_values": "Track segment, depth interval, voxel or region with dimensions", "why_it_matters": "Specifies where the reported quantity applies." }, { "name": "Density normalization", "kind": "category", "unit_or_values": "Linear LET L; mass-normalized L/ρ", "why_it_matters": "Distinguishes energy-per-length values from energy-times-area-per-mass values." }, { "name": "Evidence readiness", "kind": "state", "unit_or_values": "Convention incomplete; reproducible estimate; independently checked within a stated domain", "why_it_matters": "Controls whether the value can support comparison or further modelling." } ], "affordances": [ "Check whether a reported LET value includes enough conditions to be interpreted.", "Convert compatible units and density normalizations using a documented material density.", "Calculate or retrieve LET for a specified particle, energy, medium and restriction.", "Construct LET spectra and explicitly weighted summaries from suitable track or transport data.", "Compare LET distributions after checking conventions, particle inclusion and spatial support.", "Pass LET to a radiation-effect model only with its required context and applicability limits." ], "agent_conduct": { "may": [ "Explain linear energy transfer and how it relates to biological effects of radiation.", "Compute or look up LET values from stated particle, energy and material data." ], "must_not": [ "Give a person radiation dose or treatment advice in place of a medical physicist or clinician.", "Present LET values without stating the particle, energy, material and any cut-off used.", "Downplay or exaggerate radiation risk by misusing LET data.", "Confuse LET with absorbed dose or stopping power in safety calculations." ], "requires_human": [ "Decisions on radiotherapy plans or radiation protection that use the values." ] }, "ethics": { "considerations": [ "Radiation quality matters to patients and workers; errors can cause harm or needless fear." ], "affected_parties": [ "Radiotherapy patients", "Radiation workers", "Astronauts and aircrew" ] }, "owners": { "steward": "Nobody owns it; radiation measurement bodies maintain its definition.", "master_systems": [] }, "visual_identification": [ "Written as L or LET, usually in keV per micrometre." ], "failure_modes_and_hazards": [ "Mixing up restricted and unrestricted LET gives wrong risk estimates.", "Errors in high-LET weighting can misstate biological harm." ], "standards_and_regulation": [ "ICRU Report 85, Fundamental Quantities and Units for Ionizing Radiation, International Commission on Radiation Units and Measurements." ], "what_it_is_for": [ "Linear energy transfer is used in radiation physics and radiobiology to describe energy loss along charged-particle tracks in a material.", "It supports comparisons of radiation fields in particle therapy research, radiation protection and studies of material damage.", "Meaningful comparisons require the material, particle characteristics, secondary-electron energy cutoff and averaging convention to be specified." ] }, "sources": [ { "id": "wikidata", "title": "Wikidata item Q1699996: linear energy transfer", "url": "https://www.wikidata.org/wiki/Q1699996", "url_status": "live", "what_it_supports": "identity and sense of the item", "checked_by": "wikidata-api" }, { "id": "wikipedia-en", "title": "Wikipedia: Linear energy transfer", "url": "https://en.wikipedia.org/wiki/Linear_energy_transfer", "url_status": "live", "what_it_supports": "general description of the item", "checked_by": "wikidata-api sitelink" } ], "structure": { "bundles": [ { "id": "definition-and-restriction", "name": "Definition and restriction", "description": "Establish exactly which energy transfers and path-length convention define the reported LET.", "rationale": "Similar terminology can conceal different quantities and cutoff implementations.", "layers": [ { "id": "electronic-transfer-boundary", "name": "Electronic transfer boundary", "description": "Separate LET from total stopping power and finite-volume energy deposition.", "findings": [ { "id": "identify-defining-convention", "name": "Identify defining convention", "description": "Record the defining authority, edition and expression; unrestricted LET is numerically associated with collision stopping power. [NIST stopping-power report](https://nvlpubs.nist.gov/nistpubs/Legacy/IR/nbsir82-2550A.pdf)", "questions": [ { "text": "Which reference and mathematical definition establish the meaning of LET in this record?", "kind": "definition", "id": "identify-defining-convention-q01" }, { "text": "Does the supplied quantity include radiative or nuclear losses that place it outside that LET definition?", "kind": "boundary", "id": "identify-defining-convention-q02" } ] } ] }, { "id": "secondary-electron-restriction", "name": "Secondary-electron restriction", "description": "Make the cutoff and treatment of energetic secondary electrons explicit.", "findings": [ { "id": "resolve-cutoff-semantics", "name": "Resolve cutoff semantics", "description": "Record Δ and the exact rule for excluding energy associated with secondary electrons; verify equivalence before substituting a restricted stopping-power implementation. [ICRU Report 35](https://www.nist.gov/system/files/documents/calibrations/icru-35.pdf)", "questions": [ { "text": "What is Δ, and is the quantity restricted or explicitly unrestricted?", "kind": "measurement", "id": "resolve-cutoff-semantics-q01" }, { "text": "Does the implementation restrict secondary-electron kinetic energy, total energy transfer or another specified contribution?", "kind": "definition", "id": "resolve-cutoff-semantics-q02" } ] } ] } ] }, { "id": "particle-and-medium-conditions", "name": "Particle and medium conditions", "description": "Identify the charged particles and material to which LET applies.", "rationale": "A particle label or beam energy alone cannot identify a LET value.", "layers": [ { "id": "charged-particle-state", "name": "Charged-particle state", "description": "Describe the species and energy at the relevant track location.", "findings": [ { "id": "bind-let-to-particle-state", "name": "Bind LET to particle state", "description": "Require the particle identity, local kinetic energy and any charge-state assumptions used in calculation.", "questions": [ { "text": "Which charged-particle species and local energy or energy spectrum does the LET describe?", "kind": "measurement", "id": "bind-let-to-particle-state-q01" }, { "text": "For a photon or neutron field, which secondary charged particles supply the tracks represented by this LET?", "kind": "boundary", "id": "bind-let-to-particle-state-q02" } ] } ] }, { "id": "material-and-normalization", "name": "Material and normalization", "description": "Keep actual material, reference material and density normalization distinguishable.", "findings": [ { "id": "establish-medium-basis", "name": "Establish medium basis", "description": "Record composition, density and any conversion to a reference material such as water.", "questions": [ { "text": "Is the value LET in the traversed material or a calculated LET in a reference material?", "kind": "definition", "id": "establish-medium-basis-q01" }, { "text": "Is the reported quantity L or L/ρ, and which density and units support conversion?", "kind": "measurement", "id": "establish-medium-basis-q02" } ] } ] } ] }, { "id": "spectra-and-averaging", "name": "Spectra and averaging", "description": "Describe how a population of tracks becomes a LET distribution or summary.", "rationale": "A single average can conceal differences in particle populations and energy-transfer distributions.", "layers": [ { "id": "population-and-spatial-support", "name": "Population and spatial support", "description": "Identify included tracks and the region in which their contributions are collected.", "findings": [ { "id": "define-spectrum-support", "name": "Define spectrum support", "description": "Specify species inclusion, LET bins, spatial extent and normalization before interpreting a spectrum.", "questions": [ { "text": "Are primary particles, secondary electrons, recoil ions and nuclear fragments included or excluded?", "kind": "boundary", "id": "define-spectrum-support-q01" }, { "text": "What location, voxel size, LET binning and normalization define the distribution?", "kind": "measurement", "id": "define-spectrum-support-q02" } ] } ] }, { "id": "weighted-let-estimators", "name": "Weighted LET estimators", "description": "Make the averaging equation part of the quantity's identity.", "findings": [ { "id": "preserve-weighting-rule", "name": "Preserve weighting rule", "description": "Record track or dose weights, denominators and aggregation order; segment-based approaches also require explicit track-segment assumptions. [Segment-averaged LET research](https://aapm.onlinelibrary.wiley.com/doi/abs/10.1002/mp.13673)", "questions": [ { "text": "What exact numerator, denominator and weights define the reported average?", "kind": "definition", "id": "preserve-weighting-rule-q01" }, { "text": "Can regional LET be recomputed from underlying weighted contributions rather than an unweighted average of voxel averages?", "kind": "action", "id": "preserve-weighting-rule-q02" } ] } ] } ] }, { "id": "estimation-and-verification", "name": "Estimation and verification", "description": "Connect LET estimates to the measurements, tables or transport calculations that produced them.", "rationale": "Detector signals and simulated energy-deposition steps do not identify LET without an interpretation method.", "layers": [ { "id": "calculation-and-detector-inference", "name": "Calculation and detector inference", "description": "Document the route from raw evidence to the reported quantity.", "findings": [ { "id": "trace-let-estimator", "name": "Trace LET estimator", "description": "Record the table or transport implementation, or the detector-response inversion, together with its material and energy applicability.", "questions": [ { "text": "Which dataset, software version, physics settings or detector calibration generated the estimate?", "kind": "provenance", "id": "trace-let-estimator-q01" }, { "text": "If derived from deposited energy or lineal energy, what reconstruction makes the output an estimate of the declared LET?", "kind": "measurement", "id": "trace-let-estimator-q02" } ] } ] }, { "id": "uncertainty-and-convergence", "name": "Uncertainty and convergence", "description": "Assess whether numerical choices and evidence limitations materially change the LET result.", "findings": [ { "id": "qualify-estimate-stability", "name": "Qualify estimate stability", "description": "Track sensitivity to transport thresholds, step lengths, scoring resolution, material inputs and sampling, distinguishing numerical settings from the physical LET cutoff.", "questions": [ { "text": "How does the estimate change when step limits, production thresholds, voxel size or sample count are varied?", "kind": "measurement", "id": "qualify-estimate-stability-q01" }, { "text": "Which independent benchmark supports the stated uncertainty for this particle, medium and energy range?", "kind": "provenance", "id": "qualify-estimate-stability-q02" } ] } ] } ] }, { "id": "interpretation-and-use", "name": "Interpretation and use", "description": "Define which comparisons and downstream inferences a LET description supports.", "rationale": "LET is a radiation-quality descriptor whose usefulness depends on the question and accompanying evidence.", "layers": [ { "id": "comparison-eligibility", "name": "Comparison eligibility", "description": "Check that values describe compatible quantities before ranking or combining them.", "findings": [ { "id": "establish-comparable-let", "name": "Establish comparable LET", "description": "Require compatible restriction, medium, particle inclusion, weighting and spatial support, or an explicit justified transformation.", "questions": [ { "text": "Which defining conditions differ between these LET results, and can those differences be reconciled?", "kind": "boundary", "id": "establish-comparable-let-q01" }, { "text": "What application-specific threshold and reference population justify calling this LET high or low?", "kind": "definition", "id": "establish-comparable-let-q02" } ] } ] }, { "id": "radiation-effect-linkage", "name": "Radiation-effect linkage", "description": "Link LET to effect models without treating it as a complete prediction of damage.", "findings": [ { "id": "bound-effect-inference", "name": "Bound effect inference", "description": "Record the endpoint and response model before using an average LET to infer biological effectiveness; the adequacy of dose-averaged LET depends on response assumptions. [RBE prediction study](https://aapm.onlinelibrary.wiley.com/doi/abs/10.1002/mp.13347)", "questions": [ { "text": "Which endpoint, particle types, dose conditions and biological system support this LET-to-effect relationship?", "kind": "boundary", "id": "bound-effect-inference-q01" }, { "text": "Does the intended decision require a LET spectrum, track-structure information or other evidence beyond the reported average?", "kind": "action", "id": "bound-effect-inference-q02" } ] } ] } ] }, { "id": "evidence-and-external-alignment", "name": "Evidence and external alignment", "description": "What the world already says about this thing, gathered so the model can be checked against it.", "rationale": "A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.", "layers": [ { "id": "reported-evidence", "name": "Reported evidence", "description": "Findings from the breadth pass, kept separate from the structural claims.", "findings": [ { "id": "evidence-confidence-notes", "name": "Check these first", "description": "Recalled without web access and unsourced; every item is a lead to verify.", "evidence": [ "This account is recalled knowledge, not a source-checked review.", "Numerical LET values require particle energy, medium, cutoff and averaging convention; the range given is illustrative.", "Track-averaged and dose-averaged LET are field descriptors whose precise implementation should be checked before comparing studies." ], "questions": [ { "id": "evidence-confidence-notes-q01", "text": "Which of these check these first hold for the sense of linear energy transfer this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-kinds", "name": "Kinds and varieties", "description": "Recalled without web access and unsourced; every item is a lead to verify.", "evidence": [ "Restricted LET, with a finite secondary-electron energy cutoff", "Unrestricted LET, equivalent to electronic stopping power", "Track-averaged LET for a particle population", "Dose-averaged LET for a particle population" ], "questions": [ { "id": "evidence-kinds-q01", "text": "Which of these kinds and varieties hold for the sense of linear energy transfer this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-standards-and-regulation", "name": "Standards and regulation", "description": "Recalled without web access and unsourced; every item is a lead to verify.", "evidence": [ "ICRU Report 85a, Fundamental Quantities and Units for Ionizing Radiation, issued by the International Commission on Radiation Units and Measurements" ], "questions": [ { "id": "evidence-standards-and-regulation-q01", "text": "Which of these standards and regulation hold for the sense of linear energy transfer this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-real-world-use", "name": "Real-world use", "description": "Recalled without web access and unsourced; every item is a lead to verify.", "evidence": [ "Characterising radiation quality in radiobiology", "Analysing biological effects of proton and heavier-ion radiotherapy", "Informing radiation-protection quality factors", "Characterising charged-particle radiation fields in space", "Assessing semiconductor susceptibility to radiation-induced single-event effects" ], "questions": [ { "id": "evidence-real-world-use-q01", "text": "Which of these real-world use hold for the sense of linear energy transfer this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-measurements", "name": "Typical measurements", "description": "Recalled without web access and unsourced; every item is a lead to verify.", "evidence": [ { "quantity": "Linear energy transfer", "typical_range": "Strongly dependent on particle species, energy, material and cutoff; values in water can range from fractions of a keV/μm for fast electrons to hundreds of keV/μm for some heavy charged particles.", "unit": "keV/μm; SI unit J/m" }, { "quantity": "Mass-normalised LET", "typical_range": "Material- and particle-dependent; no universal typical range.", "unit": "MeV·cm²/mg" } ], "questions": [ { "id": "evidence-measurements-q01", "text": "Which of these typical measurements hold for the sense of linear energy transfer this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-failure-modes-and-hazards", "name": "Failure modes and hazards", "description": "Recalled without web access and unsourced; every item is a lead to verify.", "evidence": [ "Treating LET as absorbed dose: LET describes energy loss per path length, while absorbed dose describes energy imparted per mass.", "Using LET alone to predict biological effectiveness, which also depends on particle track structure, dose, endpoint and biological conditions.", "Comparing values without specifying material, secondary-electron cutoff and averaging convention.", "Equating unrestricted LET with total stopping power when nuclear stopping or radiative losses are significant.", "Assigning photons or neutrons a direct LET without accounting for the secondary charged particles that deposit energy." ], "questions": [ { "id": "evidence-failure-modes-and-hazards-q01", "text": "Which of these failure modes and hazards hold for the sense of linear energy transfer this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-neighbours", "name": "Neighbouring kinds and how to tell them apart", "description": "Recalled without web access and unsourced; every item is a lead to verify.", "evidence": [ { "name": "Stopping power", "difference": "Stopping power describes particle energy loss per path length; unrestricted LET equals its electronic component, while total stopping power can include other loss mechanisms." }, { "name": "Absorbed dose", "difference": "Absorbed dose is energy imparted per unit mass, rather than energy loss per unit particle path length." }, { "name": "Lineal energy", "difference": "Lineal energy is a stochastic microdosimetric quantity based on energy imparted in a finite site divided by its mean chord length." }, { "name": "Relative biological effectiveness", "difference": "Relative biological effectiveness compares doses producing the same biological endpoint; LET is a physical radiation quantity that influences but does not uniquely determine it." }, { "name": "Linear attenuation coefficient", "difference": "The attenuation coefficient describes the probability per unit distance of removing particles from a beam, rather than their electronic energy loss per unit distance." } ], "questions": [ { "id": "evidence-neighbours-q01", "text": "Which of these neighbouring kinds and how to tell them apart hold for the sense of linear energy transfer this model covers, and on what evidence?", "kind": "provenance" } ] } ] } ] } ] }, "openQuestions": [ "Which authoritative definition and edition should anchor the registry entry, particularly where restricted LET and restricted stopping-power conventions differ?", "Which particle species, media and energy ranges should receive validated operationalisations first?", "Which averaging and secondary-particle inclusion conventions must be supported to make records interoperable across transport codes?", "Under what detector geometries and reconstruction assumptions can measured signals provide a defensible estimate of the declared LET?", "For each intended application, when is a scalar LET summary sufficient, and when must the model require spectra or microdosimetric information?" ], "statistics": { "bundles": 6, "layers": 11, "findings": 17, "questions": 27 } }